In recent years with the development of portable devices, in order to save electric energy, in addition to a high efficiency power management integrated circuit (IC) a plurality of load switches are needed to realize the objective of supplying power to a load used by a user among the load switches and of cutting off power supply to the unused loads.
A load switch is a power supply channel component, located between a power supply and a load, which uses logic levels to control ON or OFF states, causing a load to be powered or not powered. To improve the working reliability of a traditional load switch, people have designed functions to load switches, such as the reverse current blocking (RCB) function, and correspondingly a load switch having the RCB function may be referred to as an RCB load switch.
During use, a traditional RCB load switch may be subjected to an overcurrent which flows through a power N-channel metal-oxide-semiconductor field-effect transistor (NMOSFET). Therefore, to prevent such problem, the RCB load switch is typically provided with an overcurrent protection circuit, to protect the power NMOSFET and the load.